The invention deals with the sealing of a thermal turbomachine.
The invention deals with the sealing of a thermal turbomachine according to the preamble of claim 1.
The guide and moving blades of gas turbines are subjected to high loads. In order to keep down the leakage losses of the gas turbine, the moving blade of the gas turbine is fitted relative to the stator in such a way that grazing occurs. A honeycomb structure is attached to the stator of the gas turbine in a position opposite the moving blade. The moving blades work themselves into this structure, so that a minimum sealing gap occurs between the moving blades and the honeycomb structure. The honeycomb structure consists of a heat-resistant metal alloy. It is composed of a plurality of sheet-metal strips which are bent in accordance with the subsequent shape. This construction of the honeycombs results in double-walled webs and connections of single thickness between the webs.
It is known from the prior art to arrange the double-walled webs of the honeycomb structure in the circumferential direction of the stator. However, this does not have very advantageous effects on the frictional behavior of the moving blades. Thus excessive heating may occur if the blade tip covers a plurality of honeycombs and therefore rubs continuously on the double configurations.
The aim of the invention is to overcome these disadvantages. The invention achieves the object of improving the frictional behavior between the moving blades and the honeycomb structure and of reducing the undesirable secondary effects of the friction, such as, for example, heating of the components involved.
According to the invention, the aim is achieved in a honeycomb structure in that the angle between the circumferential direction of the stator and the webs of double thickness is 5xc2x0 to 175xc2x0.
In order to achieve the same aim, the sheet thickness of the individual sheets at the points at which the sheets on the honeycomb structure form the webs may advantageously be reduced relative to the sheet thickness of the connections.
In a further embodiment, the length of the webs may be reduced in relation to the length of the connections, so that a deformed honeycomb is obtained. The ratio of the length of the webs to the length of the connections between the webs of the deformed honeycomb may be 1:1 to at most 1:20. The effect can additionally be assisted if the angle between a web and the two adjacent connections varies between 60xc2x0 and 120xc2x0.